Adjustable scaffold.



H. ERICSSON.

ADJUSTABLE SCAFFOLD.

APPLICATION FILED APR- 4, 1910.

Patented Jan.18, 1916.

2 SHEETS-SHEET I- Illllllll i H. ERICSSON.

ADJUSTABLE SCAFFOLD. APPLICATION nun) mm, 1910.

Patented Jan. 18; 1916.

2 SHEETS-SHEET 2.

HENRY ERICSSON, OF CHICAGO, ILLINOIS.

ADJUSTABLE SGAFIFOLD.

Specification of Letters Patent. Patented Jan. 18, 1916.

Application filed April 4, 1910. Serial No. 553,363.

To all whom it may concern:

Be it known that I, I'IENRY ERIEGS'SON, a citizen of the United States, residing at Chicago, in the county of Cook and State of Illinois, have invented certain new and useful Improvements in Ad ustable Scaffolds, of which the following is a description.

a side elevation of one end of the device.

My invention relates to a portable staging or platforms for use in general construction or repair work, or in any situation where a secure and rigid temporary platform may be required, especially where it is desirable to adjust the height of the platform from time to time as the work progresses.

The object of my invention is to provide a device of the kind described which shall be rigid and secure in any position and one which may be adjusted as desiredwithout interfering with the men or material upon the platform. D

To this end my invention cons1sts 1n the novel construction, arrangement and combination of parts herein shown and described and more particularly pointed out in the claims.

In the accompanying drawingswherein like or similar reference characters indicate like or corresponding parts: Figure 1, is an end elevation of my device. Fig. 2, is a side elevation of one end of the same. Fig. .3, is a section taken substantially on line 33 of Fig. 2. Fig. 4:, is a v1ew similar to Fig. 1 showing a slightly modified form of adjusting mechanism. Fig. 5, 1s

shown in Fig. 4;. Fig. 6, is a section taken substantially on line 6-6 of Fig. 5. F 1g. 7, is a fragmentary section taken substantially on line 77 of Fig. 4.

In the preferred form shown in the drawings, my device consists of a pair of similar guides 1 with a platform 2 positioned between them and slidably attached to each, so that the height of the platform may be adjusted as desired.

As shown each guide 1, comprises a pair of substantially similar parallel bars 3 rigidly connected at both ends and adapted, when in use, to stand in a substantially vertical position. For this purpose a foot 4 is provided at the lower end of each guide of suitable size and construction to afford a stable bearing for the platform and avoid any tendency to rock or tip when a load is placed upon it. At the upper end of each of the guides l the bars 3 are connected by a member 5 rigidly but preferably removably attached to each with one or more eyes or loops 6 provided so that if desired my device may be suspended from above where the desired ,height of the platform is too great, or for any other reason it cannot be practicably supported from below. The

platform 2 may be of any desired form, size,

or construction suitable for the purpose for which it is to be employed and may be slidably attached to the guides l in any convenient manner.

As shown a pair of vertical shoes or slides T are provided for each bar 3 suitably spaced from each other to receive the bar between them and snugly fit against its side faces.

A pair of cross arms or supports 8 are rigidly attached to the shoes 7 near their lower ends, suitably spaced from each other to bear upon the faces of the bars 3 to pre-' vent length-wise movement of the platform. The arms 8 are each preferably of suflicient length to receive the deck or floor 9 of the platform which is preferably rigidly but removably secured thereto to rigidly connect shown, in Figs. 1, 2 and 3. a suitable winch 12 is mounted'upon the shoes 7 witha removable crank 14 or other convenientmeans arranged to operate-the same. A pair of pulleys or sheaves 15 and 16 or equivalent means are secured to the member 5 and cross pieces 10 of'the platform respectively so that a rope or other suitable flexible member 17 may be rove through the blocks with one end attached to the member 5 as shown and the free end leading to the drum of the winch 12 so that the winch may be operated to adjust the position of the platform upon the guides and maintain the same in its adjusted position.

In the form shown in Figs. 4, 5, 6 and 7, the guides and platformsare substantially the same as hereinbefore The adjustin mechanism however consists of a substantially horizontal shaft 20 mounted in suitable bearings 21--21 uponthe shoes 7. pinion 22 is rlgidly secured to the shaft for each bar 3 and a rack 23 adapted to cooperate with the respective pinions is rigidly secured to each bar, in position to mesh with the pinions so that by-rotatmg the shaft 20 the platform 2 will be moved vertically upon the guides.

Any suitable means: may be provided to operate the shaft 20. As shown aratchet wheel 24 is rigidly secured to the shaft near one end and a lever, 25 is rotatably mounted upon the shaft with a spring actuated pawl 26 arranged to engage the teeth of the ratchet so that by oscillating the free end of the lever the shaft will be rotated. A pair of pawls 27*27 are also providedto engage the pinions 22'-22 to prevent their rotation in a reverse direction and thereby maintain the platform in its elevated position. In

theform shown, also a pair of spring actu-l ated dogs or pawls 28-'-28 are provided upon I the platform of each guide 1, each dog beparting ing arranged to engage the teeth upon one of theracks 23as an additional lock to support the platform in its elevated position.

The operation of my device is obvious and 'no'further description of the same is believed to be necessary.

Having thus described my improvement it is obvious that various immaterlal modifications may be made in my device without de from the spirit of my invention hence do not wish to be understood as lim iting myself to the exactform or construction shown.

What I claim as new and desire to secure by Letters Patent is:

1. A device of the kind described, com- I prising aplatform, a vertical guide positioned at each end of said platform, each comprising a pair of substantially independent parallel bars and a plurality of substantially independent shoes mounted upon said platform and engaging said guides to direct said platform and maintain the same in position, in combination with independent .means for each guide mounted upon and extending between the shoes for said guide said bars for and arranged to cooperate with means upon adjusting and controlling the osition of said platform.

evice of the kind described, comprising a platform, a verticalguide positloned at each end of said latforni, each comprising a pair of substantially independent parallel bars one near each corner of said platform and a plurality of substantially independent shoes mounted upon said platvertial platform and maintain the same in position, in combination with independent means for each guide mounted uponand extending between the shoes for said guide and arranged to cooperate with means upon said bars for adjusting and controlling the vertical position of said platform.

3. In a scaflt'old a plurality of platforms, a guide for eachend of said platforms, each comprising a pair of substantially parallel bars each positioned near the corner of said platforms, and a pairof shoes secured to and rigidly connectingsaid ,platforms and engagform and engaging each guide to direct said mg said bars to direct-said platforms and maintain said platforms in position, in combination with mechanism mounted upon said shoes and extending between said bars for controlling the position of said platforms.

4. A device of the kind described, com-i bars for adjusting and controlling the posi-" tion of said platform.

In testimony whereof, I have hereunto signed my name in the presence of two subscribing witnesses.

HENRY ERIOSSON. Witnesses:

BURTON U. HILLs, BLANonn CHALMaRs. 

